Human red blood cells that lack sufficient hemoglobin would have a low amount of what substance?

If a human’s red blood cells will lack sufficient amount of hemoglobin, he or she would have also a low amount of oxygen.

Hemoglobin is what makes the red blood cells red in color, aside from the abnormal color, the red blood cells also make up of oxygen. It can also be with iron since iron is bind to hemoglobin all the way to the lungs.